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    <title>Document</title>
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<body>

    <script>
        // var num = 0;
        // while (num < 5) {
        //     num = num + 1;
        //     if (num == 3) {
        //         break
        //     }
        // }
        // console.log(num);
        // sum = 0;
        // a = 0;
        // while (a++ < 3) {
        //     sum = sum + a;
        // }
        // console.log(sum);
        // console.log(sum);
        // var sum;
        // let sum = 20;
        const sum = 30;
        sum = 50;
        console.log(sum);
    </script>
</body>

</html>